Second-seeded American Sam Querrey used his high-powered serve to blast past Argentine Guillermo Canas [Images] 7-6, 6-4 in the first round of the Delray Beach International Championships on Monday.

"He makes sure you work for every point," Querrey, who sent down 13 aces and won 78 percent of points on his first serve, told reporters.

"I had a cold last week, so I was a little winded in the first set," the lanky 21-year-old Californian added. "I just tried to play to my strengths."

The world number 34 edged a first-set tiebreak after both players had dropped serve a couple of times apiece, before cashing in on a single break to win the second set over his former world top 10 opponent.

Querrey will face Christophe Rochus in the second round on Wednesday after the Belgian defeated Roko Karanusic of Croatia 6-3, 6-4.

Querrey has made it to the quarter-finals of his past two tournaments, at San Jose and Memphis, and was the runner-up at Auckland in January.

In other matches, Spaniard Guillermo Garcia-Lopez beat the fifth-seeded Steve Darcis 6-3, 6-3, handing the Belgian a fifth consecutive first-round defeat, while sixth-seeded Frenchman Florent Serra overcame Finland's Jarkko Nieminen 6-3, 7-6.

Austrian Stefan Koubek, who missed six months last season because of back surgery, also advanced with a 6-4, 6-3 win over American Bobby Reynolds.

Mardy Fish [Images] is the top seed for the $500,000 tournament and the American will open his campaign against Canadian qualifier Frank Dancevic [Images] on Tuesday.

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